Sexual dimorphism - coloration

[Andromalius]

I read an argument in one online group about sexual dimorphism in Ts, one guy said most female Ts are brighter in coloration, and another guy said the opposite (that males were brighter in coloration, he even gave examples of sps e.g. B klaasi etc.) So. Whats up with that. Lol.

 

[Oreo]

What the second guy said

 

[Andromalius]

What the second guy said

Edited post to clear thing out.

 

[EulersK]

Generalities, generalities, generalities. Sometimes, it's not a matter of being brighter:

(My male P. irminia on a breeding loan)



Female on the left, male on the right. Would you call the female "brighter"? No, it's a different color palette all together. In the case of many Poecilotheria species, the males are indeed a dull coloration of their female counterparts. However, this isn't always very obvious until the male's ultimate molt. Other genera display zero sexual dimorphism other than the males being a bit smaller.

 

[Poec54]

There is no one answer, depends on the genus/species. If there's an argument over this, they're both knuckleheads. In Poecs most females have bolder colors/markings, males tend to be drab dorsally. In the other Asian arboreals (and some terrestrials) males are a light brown, while female have vivid colors. In Pamphos, Phormics, & T apophysis, adult males have bright iridescent colors while females are usually mostly brown or black. In many genera, adult males and females have similar coloring, the most obvious difference being the male's longer legs and perpetually smaller abdomen.

 

[Andrea82]

As far as I can tell it is always the males being coloured differently, and only when maturing. However, it is not always to a brighter colour, for instance, the Psalmopoeus genus. The males turn a drab grey colour when molted to maturity.
But with Pamphobeteus platyomma, the male is brighter coloured than the female.

 

[klawfran3]

Many different Genera of spiders though don't change color. They might have dimorphism in different ways like longer legs or smaller opisthosomas, but the colors tend to stay the same. For example, look at B. Smithi, A. Geniculata, and A. Avic. All the males have the same coloration as the females when mature.

 

[bryverine]

Some more good examples that go both ways:
H. maculata males are a light brown vs a nice white on the females.
C. schioedtei on the other hand the females are darker overall where the males get that olive green color.
C. lividus (H. lividum) females are a nice blue/violet vs. that drab brown in males.
...
On and on, back and forth...